optokinetic


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nystagmus

 [nis-tag´mus]
involuntary, rapid, rhythmic movement (horizontal, vertical, rotatory, or mixed, i.e., of two types) of the eyeball. adj., adj nystag´mic.
amaurotic nystagmus nystagmus in the blind or in those with defects of central vision.
amblyopic nystagmus nystagmus due to any lesion interfering with central vision.
aural nystagmus labyrinthine nystagmus.
caloric nystagmus rotatory nystagmus in response to caloric stimuli in the ear, seen during the caloric test.
Cheyne's nystagmus a peculiar rhythmical eye movement resembling Cheyne-Stokes respiration in rhythm.
congenital nystagmus (congenital hereditary nystagmus) nystagmus usually present at birth, usually horizontal and pendular, but occasionally jerky and pendular; the nystagmus may be caused by or associated with optic atrophy, coloboma, albinism, bilateral macular lesions, congenital cataract, severe astigmatism, and glaucoma.
dissociated nystagmus that in which the movements in the two eyes are dissimilar.
end-position nystagmus that occurring only at extremes of gaze.
fixation nystagmus that occurring only on gazing fixedly at an object.
gaze nystagmus nystagmus made apparent by looking to the right or to the left.
labyrinthine nystagmus vestibular nystagmus due to labyrinthine disturbance.
latent nystagmus that occurring only when one eye is covered.
lateral nystagmus involuntary horizontal movement of the eyes.
optokinetic nystagmus nystagmus induced by looking at objects moving across the visual field.
pendular nystagmus nystagmus in which the oscillations of the eyes have an equal rate, amplitude, direction, and type of movement.
positional nystagmus that which occurs, or is altered in form or intensity, on assumption of certain positions of the head.
retraction nystagmus (nystagmus retracto´rius) a spasmodic backward movement of the eyeball occurring on attempts to move the eye; a sign of midbrain disease.
rotatory nystagmus involuntary rotation of the eyes about the visual axis.
secondary nystagmus nystagmus occurring after the abrupt cessation of rotation of the head, caused by the labyrinthine fluid continuing to move.
spontaneous nystagmus that occurring without specific stimulation of the vestibular system.
vertical nystagmus involuntary up-and-down movement of the eyes.
vestibular nystagmus nystagmus due to disturbance of the labyrinth or of the vestibular nuclei; the movements are usually jerky.

op·to·ki·net·ic nys·tag·mus

nystagmus induced by looking at moving visual stimuli.

optokinetic 

Term referring to movements of the eyes in response to the movement of objects across the visual field. Example: optokinetic nystagmus. See vestibulo-ocular reflex.
References in periodicals archive ?
When comparing GI and GIII for the saccadic eye movement tests and optokinetic nystagmus analysis, no statistically significant differences were observed (Table 1).
Aramant, "Optokinetic test to evaluate visual acuity of each eye independently," Journal of Neuroscience Methods, vol.
Nathans, "The optokinetic reflex as tool for quantitative analyses of nervous system function in mice: application to genetic and drug-induced variation," PloS One, vol.
Silencing the visual cortex led to a significant reduction in the activity of the optokinetic reflex, suggesting that it is the visual cortex that is involved in mediating the plasticity between the optokinetic and the vestibulo-ocular reflexes.
In 2012, the company announced its partnership with i2Eye Diagnostics, developing a portable, patient-friendly eye-tracking solution called Saccadic Vector Optokinetic Perimetry (SVOP), which assists clinicians in the diagnosis of ophthalmic and neurological conditions.
He became a research associate at Jichi Medical School (Tochigi, Japan) in 1986 and studied cerebellar control of optokinetic eye movements.
This is difficult for children and so, with the generous support of one of our young patient's parents, we have been able to introduce an innovative, child-friendly method of testing visual fields - a Saccadic Vector Optokinetic Perimetry (SVOP) - only the second in the UK.
(1999) Optokinetic and vestibular stimulation determines the spatial orientation of negative optokinetic afternystagmus in the rabbit.
Less well-known and yet intensely researched are microsaccades, tremor, slow drift, and vestibuloocular and optokinetic eye movements that stabilize gaze during motions of the head and motions of large regions of the image on the retina [2, 4].
These optokinetic eye movements take only fractions of a second, and the driver is not aware of them.
Neural basis of the spontaneous optokinetic response produced by visual neural inversion.
* checking for optokinetic nystagmus - one needs at least 6/60 visual acuity if this is present